Compositional analysis of water-soluble materials in corn stover

Department of Chemistry & Biochemistry, Baylor University, One Bear Place, Box 97348, Waco, Texas 76798, USA.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 08/2007; 55(15):5912-8. DOI: 10.1021/jf0700327
Source: PubMed

ABSTRACT Corn stover is one of the leading feedstock candidates for commodity-scale biomass-to-ethanol processing. The composition of water-soluble materials in corn stover has been determined with greater than 90% mass closure in four of five representative samples. The mass percentage of water-soluble materials in tested stover samples varied from 14 to 27% on a dry weight basis. Over 30 previously unknown constituents of aqueous extracts were identified and quantified using a variety of chromatographic techniques. Monomeric sugars (primarily glucose and fructose) were found to be the predominant water-soluble components of corn stover, accounting for 30-46% of the dry weight of extractives (4-12% of the dry weight of feedstocks). Additional constituents contributing to the mass balance for extractives included various alditols (3-7%), aliphatic acids (7-21%), inorganic ions (10-18%), oligomeric sugars (4-12%), and a distribution of oligomers tentatively identified as being derived from phenolic glycosides (10-18%).

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